Question

Assignment #9 Hypothesis Testing Briefly explain in your own words the advantage of using an alpha level (a) .01 versus an a .05. In general, what is the disadvantage of using a smaller alpha level? 9.1 9.2 Discuss in your own words the errors that can be made in hypothesis testing. What is a type I error? Why might it occur? What is a type Il error? How does it happen? а. b. The term error is used in two different ways in the context of a hypothesis test First, there is the concept of standard error (i.e. average sampling error), and second, there is the concept of a Type I error 9.3 What factor can a researcher control that will reduce the risk of a Type I а. error? b. What factor can a researcher control that will reduce the standard error?

Answer 1

9.2

Type I error = Rejecting null hypothesis when its true.

                                 A type 1 error is also known as a false positive and its occurs when a researcher incorrectly rejects a true null hypothesis. This means that your report that your findings are significant when in fact they have occurred by chance.

Type II = Accepting the Null hypothesis When its Falls.

                                A type II error is also known as a false negative and occurs when a researcher fails to reject a null hypothesis which is really false. Here a researcher concludes there is not a significant effect, when actually there really is.

9.3

Reducing the Risk of type I Error =

It is not possible to completely eliminate the probability of the type I error in hypothesis testing. However, there are opportunities to minimize the risks of obtaining results that contain a type I error.

One of the most common approaches to minimize the probability of getting a false positive error is to minimize the significance level of a hypothesis test. Since the significance level is chosen by a researcher, the level can be changed.

Reducing the Standard Error =

1. Increase the sample size.
2. The less that your data varies, the more precisely you can estimate a population parameter. i.e. reduce the variation in the data.
3. Use a one-sided confidence interval

i.e. A one-sided confidence interval has a smaller margin of error than a two-sided confidence interval.

4. Lower the confidence level.

The advantage of a lower confidence level is that you get a narrower, more precise confidence interval and hence the Standard error is dicreses